In today's electronics market, manufacturers are placing emphasis on increasing their product's reliability and reducing assembly costs to remain competitive. A primary focus of each manufacturer is to reduce the cost and increase the circuit density associated with interconnecting the sub-assemblies and components found within its products. Another emerging focus in today's electronics market is to pack more electronic functions into smaller packages. This means higher density modules, each requiring multiple high density interconnections to other modules.
In electrical systems, flexible printed circuits are employed as electrical jumpers or cables for interconnecting rows of terminal pins or pads of printed circuit board. Such flexible printed circuits are generally connected to a printed circuit board using a connector. Conventional connector manufacturers compete with each other using the same basic technology, individual stamped contacts molded into a plastic housing. This structure is then soldered to a printed circuit board (printed circuit board) and is then ready to receive a flexible jumper or interconnect circuit. Many of these conventional connectors are of the zero insertion force (ZIF) variety, which require the application of minimal forces during the process of inserting the flexible circuit into the connector. These ZIF connectors thus reduce the likelihood of circuit damage during the connection process.
All of today's ZIF connectors use either the edge of the interconnect circuit or a precisely located hole to accurately align the conductors of the flexible circuit to the connector's contacts. This requires circuit manufacturers to precisely control both the thickness and width of a flexible circuit's terminating ends. Generally, tolerances must be maintained within 0.003 inches. To accurately outline a circuit and control the required tolerances requires an expensive precise outline die. Another obstacle encountered in conventional circuit connector technology centers around a tendency of flexible circuits to shrink somewhat after their manufacture. When working with larger flexible circuits, the shrinkage problem can be significant enough to result in significant alignment problems. As such, outline dies are usually constrained to outline a 6 inch by 6 inch area. This size restriction adds labor costs and reduces yield.
In addition to size restrictions, flexible circuits also require the precise attachment of a support stiffener. This stiffener is required to lift the circuits into connection with a conventional connector's contacts and add the structural support necessary to ensure the thin flexible circuit enters into the connector's opening. The precise outlining and stiffener attachment process is cumbersome and costly and frequently the cause of poor yields and system failures.
Conventional connectors also utilize internal spring assemblies in order to ensure that jumpers or flexible circuits maintain adequate contact with the connector's contacts. However, until now, these connectors have incorporated a single spring assembly for each conductor. The physical size required to manufacture an acceptable spring contact eliminates this technology in high-density circuits using microminiature connectors which will eventually require conductors on 0.006 inch pitch centers.
Thus, the need for a microminiature, direct circuit to circuit connector requiring minimal manufacturing costs has led to the development of the present invention.